Ivan III (January 22, 1440 - October 27, 1505), also known as Ivan the Great (grandfather to Ivan the Terrible), was a grand duke of Muscovy who first adopted a more pretentious title of the "grand duke of all the Russias". Sometimes referred to as the "gatherer of the Russian lands", he claimed Moscow to be a Third Rome, built the Moscow Kremlin, and laid foundations for the Russian autocracy.

Background
Ivan succeeded his father Vasiliy II in 1462. Ivan tenaciously pursued the unifying policy of his predecessors. Nevertheless, cautious almost to the point of timidity, like most of the princes of the house of Rurik, he avoided as far as possible any violent collision with his neighbors until all the circumstances were exceptionally favorable. Muscovy, by this time, had become a compact and powerful state, whilst her rivals had grown perceptively weaker, a condition of things very favorable to the speculative activity of a statesman of Ivan III's peculiar character.

Gathering of Russian lands
His first enterprise was a war with the republic of Novgorod, which, alarmed at the growing dominancy of Muscovy, had placed herself beneath the protection of Casimir IV, king of Poland. Ivan took the field against Novgorod in 1470, and after his generals had twice defeated the forces of the republic during the summer of 1471 the Novgorodians were forced to sue for peace, in which they promised to abandon forever the Polish alliance, ceding a considerable portion of their northern colonies, and paying a war indemnity of 15,500 roubles.

Ivan continually sought a pretext for destroying Novgorod altogether, but though he frequently violated its ancient privileges in minor matters, the attitude of the republic was so wary that his looked-for opportunity did not come till 1477. In that year the ambassadors of Novgorod played into his hands by addressing him in public audience as Gosudar (sovereign) instead of Gospodin (sir) as heretofore. Ivan at once seized upon this as a recognition of his sovereignty, and when the Novgorodians repudiated their ambassadors, he marched against them. Deserted by Casimir IV, and surrounded on every side by the Muscovite armies, which included a Tatar contingent, the republic recognized Ivan as autocrat, and surrendered (January 14, 1478) all her prerogatives and possessions (the latter including the whole of northern Russia from Lapland to the Urals) into his hands.

Subsequent revolts (1479-1488) were punished by the removal en masse of the richest and most ancient families of Novgorod to Moscow, Vyatka and other central Russian cities. After this, Novgorod, as an independent state, ceased to exist. The rival republic of Pskov owed the continuance of its own political existence to the readiness with which it assisted Ivan against its ancient enemy. The other principalities were virtually absorbed, by conquest, purchase or marriage contract: Yaroslavl in 1463, Rostov in 1474, and Tver in 1485.

Foreign policies
It was in the reign of Ivan III that Muscovy rejected the Tatar yoke. In 1480 Ivan refused to pay the customary tribute to the grand Khan Ahmed. All through the autumn the Russian and Tatar hosts confronted each other on opposite sides of the Ugra river, till the 11th of November, when Ahmed retired into the steppe.

The further extension of the Muscovite dominion was facilitated by the death of Casimir IV in 1492. The throne of Lithuania was now occupied by Casimir's son Alexander, a weak and lethargic prince so incapable of defending his possessions against the persistent attacks of the Muscovites that he attempted to save them by a matrimonial compact, and wedded Helena, Ivan's daughter. But the clear determination of Ivan to appropriate as much of Lithuania as possible at last compelled Alexander in 1499 to take up arms against his father-in-law. The Lithuanians were routed at Vedrosha (July 14, 1500), and in 1503 Alexander was glad to purchase peace by ceding to Ivan Chernigov, Starodub, Novgorod-Seversky and sixteen other towns.

Internal policies
The character of the government of Muscovy under Ivan III changed essentially and took on an autocratic form which it had never had before. After the fall of Constantinople, orthodox canonists were inclined to regard the Muscovite grand dukes as the successors by the Byzantine emperors.

This movement coincided with a change in the family circumstances of Ivan III. After the death of his first wife Ivan III wedded the Catholic Zoe Palaeologina (better known by her orthodox name of Sophia), daughter of Thomas Palaeologus, who claimed the throne of Constantinople as the brother Constantine XI last Byzantine emperor. It was through her influence that the ceremonious etiquette of Constantinople along with the imperial double-headed eagle was adopted by the court of Moscow.

It was in the reign of Ivan III that the new Russian law code was compiled. Ivan did his utmost to make his capital a worthy successor to Constantinople, and with that object invited many foreign masters and artificers to settle in Moscow. The most noted of these was the Italian Ridolfo di Fioravante, nicknamed Aristotle because of his extraordinary knowledge, who built several cathedrals and palaces in the Kremlin. This extraordinary monument of the Muscovite art remains a lasting symbol of the power and glory of Ivan III.